Yahoo Finance editor-in-chief Andy Serwer recently spoke with Buffett, Todd Combs and Ted Weschler in an interview in Omaha. Buffett hired Combs in 2010 and Weschler in 2011 to manage some of the company's funds. The two have rarely discussed their jobs in public.

"They're chosen for both ability and character," Buffett said. "Maybe seven or eight years ago, Charlie [Munger] and I talked about the desirability of bringing on somebody or maybe more than one somebody to both manage money now, but also in preparation for the day that Charlie and I won't be around."

The two proteges now manage $10 billion of capital versus the roughly $2 billion when they first started at Berkshire, according to the legendary value investor.

Hiring the two is "one of the best decisions that Charlie and I have ever made," Buffett added.

Combs also revealed what a typical day was like as a Buffett manager:

"I get in around 7 or 8 and I read until about 7 or 8 at night. And I go home and see my family and then I'll read for another hour or two in bed at night. And you know, there might only be three to four phone calls the entire week. So there are very, very few interruptions … But it's literally just reading about 12 hours a day."

Berkshire Hathaway's annual shareholder meeting will be held on May 6.